The Intel Comet Lake Core i9-10900K, i7-10700K, i5-10600K CPU Review: Skylake We Go Againby Dr. Ian Cutress on May 20, 2020 9:00 AM EST
- Posted in
- 10th Gen Core
- Comet Lake
Socket, Silicon, Security
Editor's note: this page is mostly a carbon copy of our deep-dive covering the Comet Lake 10th Gen announcement, with some minor tweaks as new information has been obtained.
The new CPUs have the LGA1200 socket, which means that current 300-series motherboards are not sufficient, and users will require new LGA1200 motherboards. This is despite the socket being the same size. Also as part of the launch, Intel provided us with a die shot:
It looks very much like an elongated Comet Lake chip, which it is. Intel have added two cores and extended the communication ring between the cores. This should have a negligible effect on core-to-core latency which will likely not be noticed by end-users. The die size for this chip should be in the region of ~200 mm2, based on previous extensions of the standard quad core die:
CFL 4C die: 126.0 mm2
CFL 6C die: 149.6 mm2
CFL 8C die: 174.0 mm2
CML 10C die: ~198.4 mm2
Original 7700K/8700K die shots from Videocardz
Overall, Intel is using the new 10C silicon for the ten core i9 parts, as well as for the eight core i7 parts where those get dies with two cores disabled. Meanwhile for the six core i5 parts, Intel is apparently using a mix of two dies. The company has a native 6C Comet Lake-S design, but they're also using harvested dies as well. At this point it appears that the K/KF parts – the i5-10600K and i5-10600KF – get the harvested 10C design, while all of the rest of the i5s and below get the native 6C design.
For security, Intel is applying the same modifications it had made to Coffee Lake, matching up with the Cascade Lake and Whiskey Lake designs.
|Spectre and Meltdown on Intel|
|Spectre||Variant 1||Bounds Check Bypass||OS/VMM||OS/VMM||OS/VMM||OS/VMM|
|Spectre||Variant 2||Branch Target Injection||Firmware + OS||Firmware + OS||Hardware + OS||Firmware + OS|
|Meltdown||Variant 3||Rogue Data Cache Load||Hardware||Hardware||Hardware||Hardware|
|Meltdown||Variant 3a||Rogue System Register Read||Microcode Update||Firmware||Firmware||Firmware|
|Variant 4||Speculative Store Bypass||Hardware + OS||Firmware + OS||Firmware + OS||Firmware + OS|
|Variant 5||L1 Terminal Fault||Hardware||Hardware||Hardware||Hardware|
Intel has again chanced the box designs for this generation. Previously the Core i9-9900K/KS came in a hexagonal presentation box – this time around we get a window into the processor.
There will be minor variations for the unlocked versions, and the F processors will have ‘Discrete Graphics Required’ on the front of the box as well.
One of the new features that Intel is promoting with the new Comet Lake processors is die thinning – taking layers off of the silicon and in response making the integrated heat spreader thicker in order to enable better thermal transfer between silicon and the cooling. Because modern processors are ‘flip-chips’, the bonding pads are made at the top of the processor during manufacturing, then the chip is flipped onto the substrate. This means that the smallest transistor features are nearest the cooling, however depending on the thickness of the wafer means that there is potential, with polishing to slowly remove silicon from this ‘rear-end’ of the chip.
In this slide, Intel suggests that they apply die thinning to products using STIM, or a soldered thermal interface. During our briefing, Intel didn’t mention if all the new processors use STIM, or just the overclockable ones, and neither did Intel state if die thinning was used on non-STIM products. We did ask how much the die is thinned by, however the presenter misunderstood the question as one of volume (?). We’re waiting on a clearer answer.
Overclocking Tools and Overclocking Warranties
For this generation, Intel is set to offer several new overclocking features.
First up is allowing users to enable/disable hyperthreading on a per-core basis, rather than a whole processor binary selection. As a result, users with 10 cores could disable HT on half the cores, for whatever reason. This is an interesting exercise mostly aimed at extreme overclockers that might have single cores that perform better than others, and want to disable HT on that specific core.
That being said, an open question exists as to whether the operating system is set up to identify if individual cores have hyperthreads or not. Traditionally Windows can determine if a whole chip has HT or not, but we will be interested to see if it can determine which of my threads on a 10C/15T setup are hyperthreads or not.
Also for overclocking, Intel has enabled in the specification new segmentation and timers to allow users to overclock both the PCIe bus between CPU and add-in cards as well as the DMI bus between the CPU and the chipset. This isn’t strictly speaking new – when processors were driven by FSB, this was a common element to that, plus the early Sandy Bridge/Ivy Bridge core designs allowed for a base frequency adjustment that also affected PCIe and DMI. This time around however, Intel has separated the PCIe and DMI base frequencies from everything else, allowing users to potentially get a few more MHz from their CPU-to-chipset or CPU-to-GPU link.
The final element is to do with voltage/frequency curves. Through Intel’s eXtreme Tuning Utility (XTU) and other third party software that uses the XTU SDK, users can adjust the voltage/frequency curve for their unlocked processor to better respond to requests for performance. For users wanting a lower idle power, then the voltage during idle can be dropped for different multiplier offsets. The same thing as the CPU ramps up to higher speeds.
It will be interesting to see the different default VF curves that Intel is using, in case they are per-processor, per-batch, or just generic depending on the model number. Note that the users also have to be mindful of different levels of stability when the CPU goes between different frequency states, which makes it a lot more complicated than just a peak or all-core overclock.
On the subject of overclocking warranties, even though Intel promotes the use of overclocking, it isn’t covered by the standard warranty. (Note that motherboard manufacturers can ignore the turbo recommendations from Intel and the user is still technically covered by warranty, unless the motherboard does a technical overclock on frequency.) Users who want to overclock and obtain a warranty can go for Intel’s Processor Protection Plans, which will still be available.
Motherboards, Z490, and PCIe 4.0 ??
Due to the use of the new socket, Intel is also launching a range of new motherboard chipsets, including Z490, B460, and H470. We have a separate article specifically on those, and there are a small number of changes compared to the 300 series.
The two key features that Intel is promoting to users is support for Intel’s new 2.5 GbE controller, the I225-V, in order to drive 2.5 gigabit Ethernet adoption. It still requires the motherboard manufacturer to purchase the chip and put it on the board, and recent events might make that less likely – recent news has suggested that the first generation of the I225 silicon is not up to specification, and certain connections might not offer full speed. As a result Intel is introducing new B2 stepping silicon later this year, and we suspect all motherboard vendors to adopt this. The other new feature is MAC support for Wi-Fi 6, which can use Intel’s AX201 CNVi RF wireless controllers.
One big thing that users will want to know about is PCIe 4.0. Some of the motherboards being announced today state that they will support PCIe 4.0 with future generations of Intel products. At present Comet Lake is PCIe 3.0 only, however the motherboard vendors have essentially confirmed that Intel’s next generation desktop product, Rocket Lake, will have some form of PCIe 4.0 support.
Now it should be stated that for the motherboards that do support PCIe 4.0, they only support it on the PCIe slots and some (very few) on the first M.2 storage slot. This is because the motherboard vendors have had to add in PCIe 4.0 timers, drivers, and redrivers in order to enable future support. The extra cost of this hardware, along with the extra engineering/low loss PCB, means on average an extra $10 cost to the end-user for this feature that they cannot use yet. The motherboard vendors have told us that their designs conform to PCIe 4.0 specification, but until Intel starts distributing samples of Rocket Lake CPUs, they cannot validate it except to the strict specification. (This also means that Intel has not distributed early Rocket Lake silicon to the MB vendors yet.)
So purchasing a Z490 motherboard with PCIe 4.0 costs users more money, and they cannot use it at this time. It essentially means that the user is committing to upgrading to Rocket Lake in the future. Personally I would have preferred it if vendors made the current Z490 motherboards be the best Comet Lake variants they could be, and then with a future chipset (Z590?), make those the best Rocket Lake variants they could be. We will see how this plays out, given that some motherboard vendors are not being completely open with their PCIe 4.0 designs.
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DrKlahn - Wednesday, May 20, 2020 - linkMy biggest issue with gaming is that these reviews rarely show anything other than low resolution scenarios. I realize a sizable slice of the gaming community uses 1080p and that some of them are trying to hit very high frame rates. But there also a lot of us with 1440p+ or Ultrawides and I think it gets overlooked that Intels gaming "lead" largely evaporates for anyone not trying to hit very high frames at 1080p.
ElvenLemming - Wednesday, May 20, 2020 - linkHonestly, I think it's ignored because it's well understood that at 1440p+ the CPU just doesn't matter very much. There's not much value in anything above 1080p for a CPU review the vast majority of games are going to be GPU limited. That said, plenty of other outlets include them in their reviews if you want to see a bunch of charts where the top is all within 1% of each other.
DrKlahn - Wednesday, May 20, 2020 - linkI do agree with you that a lot of us do understand that as resolution and detail increases, CPUs become almost irrelevant to gaming performance. However you do see a fair few posters parroting "Intel is better for gaming" when in reality for their use case it really isn't any better. That's why I feel like these reviews (here and elsewhere) should spotlight where this difference matters. If you are a competitive CS:GO player that wants 1080p or lower with the most frames you can get, then Intel is undoubtedly better. But a person who isn't as tech savvy that games and does some productivity tasks with a 1440p+ monitor is only spending more money for a less efficient architecture that won't benefit them if they simply see "Intel better for gaming" and believe it applies to them.
shing3232 - Thursday, May 21, 2020 - link3900X or 3800X can beat Intel 9900Kf on csgo with pbo on if I remember correctly.
silencer12 - Saturday, May 23, 2020 - linkCsgo is not a demanding game
vanilla_gorilla - Monday, June 15, 2020 - link>If you are a competitive CS:GO player that wants 1080p or lower with the most frames you can get, then Intel is undoubtedly better.
It's actually more complicated than that. Even midrange Zen 2 CPU can hit well over 200 fps in CS:GO. So unless you have a 240hz monitor, it won't make any difference buying Intel or AMD in that case.
Irata - Wednesday, May 20, 2020 - linkTechspot shows a seven game average and there the avg fps / min 1% difference to the Ryzen 3 3300x is less than 10% using a 2080ti.
CrimsonKnight - Thursday, May 21, 2020 - linkThis review's benchmarks goes up to 4K/8K resolution. You have to click the thumbnails under the graphs.
Meteor2 - Wednesday, July 15, 2020 - linkTo be clear: Anandtech tests at low resolutions so the bottleneck is the CPU, not the GPU. A Ryzen 5 won’t bottleneck a 2080 Ti at 4K.
kmmatney - Wednesday, May 20, 2020 - linkThose of us who live near a Microcenter can get the 3900X for $389, along with a $20 discount on a motherboard (and a serviceable heatsink). The Ryzen 5 (what I bought) is $159, also with a $20 motherboard discount and a decent cooler. So my effective motherboard cost was $79, and total cost of $240 + tax, with a motherboard that can (most likely) be upgraded to Zen 3